1. Field of the Invention
The present invention relates to a process for manufacturing a film-type packaging material, a device for carrying out the process and the use of the packaging material.
2. Background Art
Various forms of packaging with sealing seam closures are widely used as the production of such closures is extremely simple and cost-favorable, and, e.g., in many cases meet the requirements of one-way packaging.
The production of so-called sealing lacquer coatings on films or film-type laminates is as a rule carried out using conventional lacquer deposition methods such as e.g. roll-coating, immersion coating or nozzle-spray coating. Also known is the deposition of sealing lacquer coatings using intaglio printing methods. The coating is normally deposited over the whole surface area. This means that also areas of the packaging material which are not intended to be sealing areas are also coated with a sealing lacquer. Using a so-called intaglio printing method it is also possible to deposit the sealing layer locally i.e. over only part of the surface.
The sealing coatings are, e.g., cold-sealing or hot-sealing lacquers. Cold-sealing lacquers normally have a latex-base and are employed especially for heat-sensitive goods. Hot-sealing lacquers which are adhesives that can be activated thermally are, e.g., in the form of polymers. They are, as a rule, deposited on the packaging material in the form of solutions (lacquers) or in the form of films of a polymeric material.
The conventional production methods suffer the disadvantage that the sealing layers or sealing lacquer layers can be deposited only over the whole surface or only to a limited extent over part of the surface. Further, setting up the production facilities for localized deposition of the sealing layer is complicated, therefore, local deposition can not simply be changed at will. Further, solvent containing lacquers are not completely free of problems from the environmental standpoint and should, therefore, be replaced by solvent-free coating systems.